Trombone



Jan. 20, 1931. A. J. JOHNSON TROMBONE Filed Aug. 5. 1929 A TTORNE Y SPatented Jan. 20, 1931' UNITED STATES PATENT OFFICE ALFRED J. JOHNSON,OF GRAND RAPIDS, MICHIGAN, ASSIGNOR TO YORK BAND IN- STRUMENT COMPANY,OF GRAND RAPIDS, MICHIGAN TROMBONE Application filed August 5, 1929.Serial No. 888,691.

This invention relates to improvements in slide trombones and it relatesparticularly to the improvement of the slide.

The objects of the invention are:

First, to provide such a slide which will be very easy in operation andin which binding, due to slight defects or damage to the outer tube, areavoided.

Second, to provide an improved arrangement of the slide shoe, carryingthe same by the outer member of the slide as distinguished from theinner.

Objects pertaining to details will appear from the description tofollow. A preferred embodiment of my invention is illustrated in theaccompanying drawing, in which:

Fig. l is a side elevation view of a trombone embodying the features ofmy invention.

Fig. 2 is an enlarged detail elevation view of the slide structure.

The parts will be identified by their numerals of reference which arethe same in both the views.

1, l are the frame members of the trombone connected by the cross handle2. 3,3 are the inner slideway members which are plain, straight tubemembers coupled by the cross loop 41. 5 are the shoes which are Waytubes open at their inner ends secured to the frame thereof, telescopetube members loosely surrounding the same in spaced relation connectedby a loop at their outer ends, slideway shoes having inner spirallubricant grooves and disposed at the inner ends of said outer tubemembers, and outer sleeves con- 7 ALFRED J. JOHNSON.

coupled to the telescope tube members by the sleeves 6, 6. The shoes 5are each provided with an inner spiral lubricant groove 51. The sleeves6, 6 are connected by the cross handle 7 by which the entire slide ismanipulated in playing the instrument.

The tube members 4 have a bore of about four thousandths of an inchlarger than the slideway members 3, and consequently if they becomeslightly dented or otherwise injured or are slightly irregular in form,they do not bind on the slideway and manipulation is free and easy as aconsequence. A sli ht blow on the outer member 4 does not inter ere withthe free operation of the structure.

I desire to claim this structure in its specific form.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent, is:

In a slide trombone, the combination with the instrument frame of a pairof inner slide-

